Rotor assembly for an electric machine

Abstract

The present disclosure relates to a rotor assembly for an electric machine. The rotor assembly comprises a rotating shaft, a rotor and a fluid cooling system. The rotor is fixed to the rotating shaft. The rotor comprises a rotor core, a first end plate and a second end plate. The first end plate is provided at a first axial end of the rotor core. The second end plate is provided at a second axial end of the rotor core. The fluid cooling system comprises at least one fluid cooling pathway provided internally in the rotor. The at least one fluid cooling pathway is configured to guide cooling fluid through the rotor, and comprises at least one cooling channel and a downstream end plate channel. The at least one cooling channel extends through the rotor core from the first axial end to the second axial end. The downstream end plate channel is fluidically connected to a downstream end of the at least one cooling channel. The downstream end plate channel is restricted radially outwards by a radially outer wall portion. The at least one cooling channel is restricted radially inwards by a radially inner wall portion. A radially innermost position of the radially outer wall portion is arranged in a range about or at or radially inwards of a radially innermost position of a radially inner wall portion.